How to setup particles rotation to follow the camera?
Issue resolved. I am attaching the new file for details also adding some words and screenshots for faster resolution.

Check the Advanced tab under particle settings. It will open the
Rotation tab between Velocity and Physics.

Check that Rotation option and tweak the Orientation &amp; Phase to get the desired result.

Use the &quot;Track to&quot; constrain for the mother particle with the
Camera. (no other tracking constrain has that much flexibility.)


**don't forget to set the origin in the right place for the mother Particle (for the cat image it's at the bottom middle where the 3d cursor is in the 1st image.) To set the origin in Custom places you must go into Edit Mode the select the corresponding vertex/edge press Shift + &quot;S&quot; then select Cursor TO Selected. get out of edit mode select the Mesh and right-click &gt;&gt; Set Origin &gt;&gt; to 3D Cursor.
***setting the cursor to the selected edge will place that at the middle of that edge. If you want more freedom make a loop cut at the exact point you want to place the Cursor/origin and select only that vertex in the edit mode. Then do as previous.
Screenshots-


Here is the link- &gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt; https://drive.google.com/file/d/1Os-NCiLtDF0AkZP4hDP5Qc6NGPT3yC1s/view?usp=sharing.